package com.cyh.testdesignpattern.appearance;

import android.util.Log;

//屏幕
public class Screen {
    private static Screen instance = new Screen();
    public static Screen getInstance() {
        return instance;
    }

    public void up() {
        Log.i("Screen", "Screen up");
    }

    public void down() {
        Log.i("Screen", "Screen down");
    }

}
